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Changes to the Ice Wall page on the wiki
« on: August 11, 2021, 08:36:55 PM »
As the wiki is variably described in the fora as a compilation of data and arguments that underpin FET based on a collection of scholarly sources, I thought I'd take up a recommendation to make some suggestions on ways to improve the page on the ice wall.

In general: many more sources are required, the page should be better organized to separate information on the known physical characteristics of the wall with theorized conjecture of what may lie beyond it on earth's vast plane, it is striking that descriptions stop after James Ross' first(?) account, there are several inconsistencies between this page and others (isostasy and mountains and volcanoes pages), and several terms are misused.

Video:
Citation needed for source of footage

First paragraph:
The first few sentences are, in essence, all dopplegangers of each other. Would it not be simpler to write something that encompasses those ideas into one? ‘the ice wall is a series of massive walls of ice that surrounds/forms most of the coast of Antarctica, rising vertically from the ocean 150 feet (50m) and extending to depths of several hundred metres or more’

2nd:
Mentioned search for south magnetic pole; this concept should be tidied up later in article

Quote from James Clark Ross:
Citation is needed for source of quote.

indicates the ice wall is not the edge of the known/knowable world
Quote
the intensely bright sky beyond it (the ice wall) but too plainly indicated the great distance to which it reached southward
this last part of the quote also suggests that all that region beyond the ice wall should be something TFES concerns itself with, as is laid out in the introductory sentence
Quote
the area which the light from the sun affects

Citation is needed for the quote.

4th:
Ross vainly searched for passage through a southern sea but failed.  But he wasn’t the last to try to find the south magnetic pole or explore the continent, something any discerning reader of the page should pick up on. More recent explorers have ventured inland, using modes of transportation suitable for land travel – Carl Anton Larsen became the first to ski on the Antarctica in 1892-1893, the Belgians were the first to overwinter in Antarctica in 1897-1899, Robert Falcon Scott reached 82degS during the Discovery expedition 1901-1904; and after a decade of intense exploration by many countries, Prof. Edgeworth David reached the south magnetic pole on Jan 16, 1909 (full list provided here: https://en.wikipedia.org/wiki/List_of_Antarctic_expeditions).

This brings things back to south magnetic pole mentioned in paragraph 2. Why is Ross’ account of his journey to be held as truth, but none of the subsequent accounts, whose leads actually planned for terrestrial travel and harsh winter conditions. In modern times, multiple countries have established research stations, like the Amundsen-Scott station at the south pole.

5th:
Quote
beyond the ice wall is anyone’s guess.
This statement is contradictory to the evidence provided in the page’s lone scholarly source, Drewry (1983)’s compilation. While the book is not available online, but can be ordered for 59 pounds (in 1983), a book review by C. Lorius from the Laboratoire de Glaciologie et Geophysique de l’Environment in Grenoble indicates in includes radio echo sounding data for ‘about half of Antarctica’, which build upon classical techniques like seismic studies, and other recent developments like Landsat satellite Imagery. Basic data are summarized in a series of maps featuring surface and bedrock topography, ice sheet thickness, residual magnetic field, and internal layering of the ice sheet (find full review here: https://www.cambridge.org/core/services/aop-cambridge-core/content/view/812955488EB01D7340B69CA3EBF76682/S0032247400005490a.pdf/antarctic-glaciology-and-geophysics-antarctica-glaciological-and-geophysical-folio-david-j-drewry-editor-1983-cambridge-scott-polar-research-institute-iv-9-folios-5-to-be-added-maps-hard-cover-isbn-09.pdf). If Drewry’s compilation includes all those data sets, and those data are inherently supported in the wiki, then they should be useful in ascertaining the nature of the ice wall, including the source(s) of ice that create it. Take for instance Siegert et al. 2005’s paper on Radio echo sounding data covering the entire region between the Ronne and Ross ice shelves, which passes by the south pole (DOI: 10.1002/esp.1238).

Quote
all we at present know is, that snow and hail, howling winds, and indescribable storms and hurricanes prevail
antarctica is absolutely one of the least hospitable regions on earth.

Has there ever been a hurricane there?

I would point to research station live streams, the results from atmospheric observation stations and other observatories, as well as the accounts (and crappy selfies) from travellers that collectively indicate that it’s not exactly desolate, given that several tens of thousands of tourists visit every year (https://www.coolantarctica.com/Antarctica%20fact%20file/science/threats_tourism.php), including many who go swimming – if I had $75K I’d be there in a heart beat, but that’s unfortunately neither here nor there.

Quote
human ingress is barred by unsealed escarpments of perpetual ice
there is no context for this quote. We’re only left to assume it’s another excerpt from James Clark Ross, but that should be clarified and cited.

 as alluded to earlier, human ingress has never really been stopped by a 150-foot wall, unless you’re stuck in a boat.

FORMATION

Photo caption:
add in-text citation to Drewry 1983

1st paragraph:
Most of the ice wall (51%) is grounded, not floating ice, according to the table provided in following section

Suggest an alternate formulation of next sentence: ‘Ice wall is formed from and fed by glaciers extending northward from areas lying at higher elevations than the ice wall observed at the southern shoreline of the southern Ocean.
Even without going beyond the ice wall, physical laws indicate there must be a driving force to induce northward flow of ice, which can only be achieved by having the ice sourced at higher elevations. Happy to provide general sources for that, but it’s really just a matter of agreeing that water doesn’t flow uphill.

Not a critical point at all, but it’s not the presence or strength of currents that controls whether the ice wall will be grounded or occur as a floating ice shelf. And actually, its ice dynamics and meltwater drainage that exerts a strong control on local ocean currents. It’s more about interactions between ice flux and basin geometry (shape, bed gradients, bathymetry), but it’s at least partially fair to say that warm ocean currents can undercut the ice wall, which leads to instability and can promote enhanced calving rates (the primary fear regarding future global warming triggering enhanced calving and accelerating sea level rise)

2nd:
Citation needed to explain the ‘series of ice walls’ and presence of Transantarctic mountain Ranges.

Would recommend also linking these to the Wiki page on mountains and volcanoes, but it’s unclear what type of FE mountains the Transantarctic range is (citation needed), or how it relates to the wiki-postulated subduction zone beneath the ice wall on the volcanoes page. A recent open access paper in Earth-Science Reviews may be of use (https://www.sciencedirect.com/science/article/pii/S0012825221000507#f0005)

Citation needed for figures on magnitude of isotatic depression.

Suggestion of isostatic depression of bedrock beneath the ice wall is at odds with views covered on isostasy page.

Citation needed on Ice streams (recommend Bennett 2002; Livingstone et al 2012; or http://www.antarcticglaciers.org/glacier-processes/glacier-types/ice-streams/).

Ice streams do not ‘flow through’ the ice wall, the ice wall forms along the calving margin of ice streams

3rd:
General comment - this paragraph should have its own subheading so it is not confused with the description of the nature of the ice wall. Nothing is this paragraph is about the formation of the ice wall.

What is the basis for proposing temperatures may approach absolute zero south of the ice wall?

Why is it assumed to be pitch black when Ross’ account and the video provided at the top of the page all indicate the entire (visible) region is affected by sunlight?

Recommend expanding on the concept of “vast plane of unknown diameter” to distance the views promoted here with the more fringe(?) views of the ice wall as the ‘edge’ or part of the dome, etc. these views create a physical impossibility in this region given that the ice flowing northward to create the ice walls require a source area (discussed above and in references provided)

ANTARCTIC COASTAL TYPES:
Ignoring all data collected by man and machine after 1983 is anything BUT “current”.
The percentages of coastal types are not a ‘frequency’.